The Cover Feature highlights the concept that, for water-splitting reaction and related clean energy technology, it is imperative to design earth-abundant low-cost electrocatalysts. In this spirit, the work by Abhisek Padhy, Prabeer Barpanda, and co-workers introduces double perovskite-based strontium cobalt molybdenum oxide (SCMO) as an efficient bifunctional electrocatalyst showing both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Prepared by scalable autocombustion synthesis, the bulk SCMO perovskite exhibits stable electrocatalytic performance attributed to its substantial electrochemical active surface area. Double perovskite electrocatalysts can be harnessed for sustainable energy technologies. More information can be found in the Research Article by Shahan Atif et al. (DOI: 10.1002/cctc.202400217).
{"title":"Cover Feature: Bifunctional Strontium Cobalt Molybdenum Oxide (Sr2CoMoO6) Perovskite as an Efficient Catalyst for Electrochemical Water Splitting Reactions in Alkaline Media (ChemCatChem 17/2024)","authors":"Shahan Atif, Abhisek Padhy, Pawan Kumar Jha, Dorothy Sachdeva, Dr. Prabeer Barpanda","doi":"10.1002/cctc.202481702","DOIUrl":"https://doi.org/10.1002/cctc.202481702","url":null,"abstract":"<p><b>The Cover Feature</b> highlights the concept that, for water-splitting reaction and related clean energy technology, it is imperative to design earth-abundant low-cost electrocatalysts. In this spirit, the work by Abhisek Padhy, Prabeer Barpanda, and co-workers introduces double perovskite-based strontium cobalt molybdenum oxide (SCMO) as an efficient bifunctional electrocatalyst showing both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Prepared by scalable autocombustion synthesis, the bulk SCMO perovskite exhibits stable electrocatalytic performance attributed to its substantial electrochemical active surface area. Double perovskite electrocatalysts can be harnessed for sustainable energy technologies. More information can be found in the Research Article by Shahan Atif et al. (DOI: 10.1002/cctc.202400217).\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure>\u0000 </p>","PeriodicalId":141,"journal":{"name":"ChemCatChem","volume":"16 17","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cctc.202481702","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142165619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bohai Gao, Weijie Li, Yuchao Chai, Guangjun Wu, Landong Li
The catalytic cycloaddition of CO2 to epoxides to produce valuable cyclic carbonates represents a simple and promising strategy for CO2 utilization, circumventing the ineffective CO2 reduction process. Despite current progresses, there remains an impending demand for highly‐active, cost‐effective and stable catalysts especially the ideal heterogeneous catalytic systems. Herein, we report the preparation of heteroatom‐containing zeolites through a two‐step process comprising of framework dealumination and subsequent heteroatom incorporation, and their catalytic applications in CO2 cycloaddition to epoxides. Characterization results reveal the successful incorporation of heteroatoms into framework to derive Lewis acidic M‐Beta zeolites (M=Ti, Zr or Hf). The as‐prepared M‐Beta Lewis acids show remarkable performance in the model reaction of CO2 cycloaddition to propylene oxide with the assistance of potassium iodide under solvent‐free conditions. The reaction parameters have been optimized employing Ti‐Beta catalyst and the substrate scope has been investigated. Finally, the impact of Lewis acidity on the cycloaddition reaction is discussed and the actual bifunctional Ti‐Beta/KI catalyst system is proposed, which is of important significance for the understanding of CO2 catalytic cycloaddition to epoxides.
将二氧化碳催化环化加成到环氧化物中，生成有价值的环状碳酸盐，是一种简单而有前途的二氧化碳利用策略，可避免无效的二氧化碳还原过程。尽管目前取得了一些进展，但对高活性、高成本效益和稳定的催化剂，尤其是理想的异相催化体系的需求仍迫在眉睫。在此，我们报告了通过两步法制备含杂原子沸石的过程，包括框架脱铝和随后的杂原子加入，以及它们在环氧化物的 CO2 环加成中的催化应用。表征结果表明，杂原子成功地加入到框架中，从而得到了路易斯酸型 M-Beta 沸石（M=钛、锆或铪）。在无溶剂条件下，在碘化钾的帮助下，制备的 M-Beta 路易斯酸在二氧化碳与环氧丙烷的环加成模型反应中表现出了卓越的性能。利用 Ti-Beta 催化剂对反应参数进行了优化，并对底物范围进行了研究。最后，讨论了路易斯酸对环加成反应的影响，并提出了实际的双功能 Ti-Beta/KI 催化剂体系，这对理解 CO2 催化环加成环氧化物具有重要意义。
{"title":"Heteroatom‐Containing Zeolites as Solid Lewis Acid Catalysts for the Cycloaddition of CO2 to Epoxides","authors":"Bohai Gao, Weijie Li, Yuchao Chai, Guangjun Wu, Landong Li","doi":"10.1002/cctc.202401385","DOIUrl":"https://doi.org/10.1002/cctc.202401385","url":null,"abstract":"The catalytic cycloaddition of CO2 to epoxides to produce valuable cyclic carbonates represents a simple and promising strategy for CO2 utilization, circumventing the ineffective CO2 reduction process. Despite current progresses, there remains an impending demand for highly‐active, cost‐effective and stable catalysts especially the ideal heterogeneous catalytic systems. Herein, we report the preparation of heteroatom‐containing zeolites through a two‐step process comprising of framework dealumination and subsequent heteroatom incorporation, and their catalytic applications in CO2 cycloaddition to epoxides. Characterization results reveal the successful incorporation of heteroatoms into framework to derive Lewis acidic M‐Beta zeolites (M=Ti, Zr or Hf). The as‐prepared M‐Beta Lewis acids show remarkable performance in the model reaction of CO2 cycloaddition to propylene oxide with the assistance of potassium iodide under solvent‐free conditions. The reaction parameters have been optimized employing Ti‐Beta catalyst and the substrate scope has been investigated. Finally, the impact of Lewis acidity on the cycloaddition reaction is discussed and the actual bifunctional Ti‐Beta/KI catalyst system is proposed, which is of important significance for the understanding of CO2 catalytic cycloaddition to epoxides.","PeriodicalId":141,"journal":{"name":"ChemCatChem","volume":"47 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael A Unkrig-Bau, Sara L Leijendekker, Jan Streuff
The synthesis of one achiral and two chiral propylene‐bridged dititanocenes and their evaluation as catalysts in titanium(III) catalyzed ketone‐nitrile coupling reactions is reported. A reaction progress kinetics analysis of the cross‐coupling between acetophenone and benzyl cyanide reveals that, using a dinuclear titanocene catalyst, the order in catalyst is reduced from two to one in comparison to a mononuclear catalyst. Although the obtained coupling yields and enantioselectivities did not reach the results obtained with the latter, these examples constitute a proof‐of‐concept for the templated C‐C coupling through coordination of ketone and nitrile to the two tethered titanium centers of a dinuclear catalyst.
{"title":"Exploring Dinuclear Titanium Complexes in Titanium(III) Catalysis","authors":"Michael A Unkrig-Bau, Sara L Leijendekker, Jan Streuff","doi":"10.1002/cctc.202401337","DOIUrl":"https://doi.org/10.1002/cctc.202401337","url":null,"abstract":"The synthesis of one achiral and two chiral propylene‐bridged dititanocenes and their evaluation as catalysts in titanium(III) catalyzed ketone‐nitrile coupling reactions is reported. A reaction progress kinetics analysis of the cross‐coupling between acetophenone and benzyl cyanide reveals that, using a dinuclear titanocene catalyst, the order in catalyst is reduced from two to one in comparison to a mononuclear catalyst. Although the obtained coupling yields and enantioselectivities did not reach the results obtained with the latter, these examples constitute a proof‐of‐concept for the templated C‐C coupling through coordination of ketone and nitrile to the two tethered titanium centers of a dinuclear catalyst.","PeriodicalId":141,"journal":{"name":"ChemCatChem","volume":"262 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jinju Hong, Jonghyun Jeon, Hee Hwan Kim, Kyung Soo Shin, Sung June Cho, Kyoung-Su Ha
Two types of thin zeolite MCM‐22 catalysts were prepared by using a carbon sphere template. By different calcination methods, a hollow sphere‐type MCM‐22 (HS‐MCM‐22) and a nanosheet‐type MCM‐22 (NS‐MCM‐22) were synthesized. Those catalysts were tested and evaluated for acetylene aromatization to see the effects of thin structures. The two types of thin catalysts were found to have higher amount of acid sites than that of the conventional MCM‐22 catalyst. It was found that the extremely short diffusion length not only enhanced the aromatic yield, but also suppressed the formation of graphitic coke. Notably, the diffusion length of NS‐MCM‐22 was found to be at least 15 times shorter than that of conventional MCM‐22, leading to an 11 % and 18 % increase in benzene yield, respectively. The thin structure seemed to help the produced aromatics efficiently desorb before they further converted into carbon precursors and coke. The carbon species in the spent thin catalysts were found less graphitic than that of the conventional MCM‐22 catalyst. Because of this, the thin MCM‐22 catalysts were believed to show higher coke removal capability. Especially, the coke removal rate of NS‐MCM‐22 was estimated over 90% despite the severe carbon deposition during reaction.
{"title":"Effects of Acid Sites on Thin MCM‐22 Zeolite Catalysts and Their Catalytic Applications for Acetylene Aromatization","authors":"Jinju Hong, Jonghyun Jeon, Hee Hwan Kim, Kyung Soo Shin, Sung June Cho, Kyoung-Su Ha","doi":"10.1002/cctc.202401302","DOIUrl":"https://doi.org/10.1002/cctc.202401302","url":null,"abstract":"Two types of thin zeolite MCM‐22 catalysts were prepared by using a carbon sphere template. By different calcination methods, a hollow sphere‐type MCM‐22 (HS‐MCM‐22) and a nanosheet‐type MCM‐22 (NS‐MCM‐22) were synthesized. Those catalysts were tested and evaluated for acetylene aromatization to see the effects of thin structures. The two types of thin catalysts were found to have higher amount of acid sites than that of the conventional MCM‐22 catalyst. It was found that the extremely short diffusion length not only enhanced the aromatic yield, but also suppressed the formation of graphitic coke. Notably, the diffusion length of NS‐MCM‐22 was found to be at least 15 times shorter than that of conventional MCM‐22, leading to an 11 % and 18 % increase in benzene yield, respectively. The thin structure seemed to help the produced aromatics efficiently desorb before they further converted into carbon precursors and coke. The carbon species in the spent thin catalysts were found less graphitic than that of the conventional MCM‐22 catalyst. Because of this, the thin MCM‐22 catalysts were believed to show higher coke removal capability. Especially, the coke removal rate of NS‐MCM‐22 was estimated over 90% despite the severe carbon deposition during reaction.","PeriodicalId":141,"journal":{"name":"ChemCatChem","volume":"55 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Agnès Labande, Illia Ruzhylo, Anna Vorozhbian, Sandrine Vincendeau, Tanguy Saget, Sonia Mallet-Ladeira, Philippe Dauban, Eric Manoury
[Rh2(phesp)2], a new dirhodium(II) complex bearing a bulky bidentate bis‐carboxylate ligand, has been prepared in two steps from commercially available compounds. Its X‐ray structure revealed distinctive features with a strong distortion around the dirhodium(II) core, illustrated by important torsion angles of up to 9.0°. It has been evaluated as catalyst as a bulky version of the prominent [Rh2(esp)2] complex in carbene C–H insertion reactions. [Rh2(phesp)2] proved as active as [Rh2(esp)2], and showed an intermediate selectivity between [Rh2(esp)2] and bulky [Rh2(tpa)4] in both intra‐ and intermolecular reactions with donor‐acceptor and acceptor‐acceptor diazo compounds, comprising challenging C(sp3)–H insertion into pentane.
[Rh2(phesp)2]是一种新的二铑(II)配合物，带有笨重的双齿双羧酸配体，由市售化合物通过两个步骤制备而成。它的 X 射线结构显示出与众不同的特征，即在二铑(II)核心周围有强烈的畸变，重要的扭转角高达 9.0°。在碳烯烃 C-H 插入反应中，它作为著名的[Rh2(esp)2]复合物的膨大版催化剂进行了评估。事实证明，[Rh2(phesp)2]与[Rh2(esp)2]具有同样的活性，而且在与供体-受体和受体-受体重氮化合物的分子内和分子间反应中，其选择性介于[Rh2(esp)2]和笨重的[Rh2(tpa)4]之间。
{"title":"[Rh2(phesp)2]: a Bulkier [Rh2(esp)2] Analog to Tune the Site‐Selectivity in Carbene C–H Insertion Reactions","authors":"Agnès Labande, Illia Ruzhylo, Anna Vorozhbian, Sandrine Vincendeau, Tanguy Saget, Sonia Mallet-Ladeira, Philippe Dauban, Eric Manoury","doi":"10.1002/cctc.202400874","DOIUrl":"https://doi.org/10.1002/cctc.202400874","url":null,"abstract":"[Rh2(phesp)2], a new dirhodium(II) complex bearing a bulky bidentate bis‐carboxylate ligand, has been prepared in two steps from commercially available compounds. Its X‐ray structure revealed distinctive features with a strong distortion around the dirhodium(II) core, illustrated by important torsion angles of up to 9.0°. It has been evaluated as catalyst as a bulky version of the prominent [Rh2(esp)2] complex in carbene C–H insertion reactions. [Rh2(phesp)2] proved as active as [Rh2(esp)2], and showed an intermediate selectivity between [Rh2(esp)2] and bulky [Rh2(tpa)4] in both intra‐ and intermolecular reactions with donor‐acceptor and acceptor‐acceptor diazo compounds, comprising challenging C(sp3)–H insertion into pentane.","PeriodicalId":141,"journal":{"name":"ChemCatChem","volume":"25 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In nature, catechol oxidase catalyzes the oxidation of o‐diphenol to o‐quinone to produce a series of highly important polyphenolic natural products. Although mimicking the functionality of natural enzyme using a nanozyme was found to be beneficial, attaining a high specificity is challenging. Herein, we have explored the thickness‐dependent oxidase activity and specificity of Cu‐metal‐organic framework (MOF) nanosheets. The unique synthetic method offers control over the thickness of the Cu‐MOF nanosheets. The ultrathin (4 nm) Cu‐MOF (Cu‐UMOF) nanosheets as an oxidase nanozyme exhibit high specificity for catechol oxidation without having any peroxidase activity. Interestingly, the specificity is lost for the thicker (20‐30 nm) Cu‐MOF nanosheets. The binuclear Cu‐center, coordinative and electronic unsaturation tuned electronic structure in Cu‐UMOF, resulting in higher specificity for catechol oxidation than thicker Cu‐MOF.
{"title":"Oxidase‐like nanozyme activity of ultrathin copper metal‐organic framework nanosheets with high specificity for catechol oxidation","authors":"Ajit Kumar Singh, Deepika Sharma, Devesh Kumar Singh, Sonu Sarraf, Aviru Kumar Basu, Vellaichamy Ganesan, Avishek Saha, Arindam Indra","doi":"10.1002/cctc.202401029","DOIUrl":"https://doi.org/10.1002/cctc.202401029","url":null,"abstract":"In nature, catechol oxidase catalyzes the oxidation of o‐diphenol to o‐quinone to produce a series of highly important polyphenolic natural products. Although mimicking the functionality of natural enzyme using a nanozyme was found to be beneficial, attaining a high specificity is challenging. Herein, we have explored the thickness‐dependent oxidase activity and specificity of Cu‐metal‐organic framework (MOF) nanosheets. The unique synthetic method offers control over the thickness of the Cu‐MOF nanosheets. The ultrathin (4 nm) Cu‐MOF (Cu‐UMOF) nanosheets as an oxidase nanozyme exhibit high specificity for catechol oxidation without having any peroxidase activity. Interestingly, the specificity is lost for the thicker (20‐30 nm) Cu‐MOF nanosheets. The binuclear Cu‐center, coordinative and electronic unsaturation tuned electronic structure in Cu‐UMOF, resulting in higher specificity for catechol oxidation than thicker Cu‐MOF.","PeriodicalId":141,"journal":{"name":"ChemCatChem","volume":"73 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A highly porous NiAl2O4 spinel structure was synthesized and employed as a support for catalysts in the autothermal dry reforming of methane (ATDRM) in a monolithic‐type reactor. A series of catalyst with various metal species, X/NiAl2O4@monolith (X: Ni, Co, Pt, Rh, and Ru), was prepared. NiAl2O4 support provides a high dispersion of active metal species with a uniform size distribution, due to its high surface area, and large pore volume. These features enable catalysts to maximize catalytic performance by improving the adsorption and reaction rates of reactants. More notably, the use of NiAl2O4 support enhanced catalyst longevity by retarding coke formation during the ATDRM, due to its improved catalyst acidity compared to conventional alumina support. The conversion of feeed, CH4 and CO2 on X/NiAl2O4 catalysts increases in the order of Rh > Ni > Ru > Co > Pt. Notably, the inexpensive Ni catalyst exhibits slightly lower but comparable CH4 conversion to the expensive noble metal Rh when using NiAl2O4 as a supporting material: 93.7% for Ni vs. 95.2% for Rh. Moreover, applying monolithic reactors considerably increased methane conversion compared with fixed bed reactors due to the better distribution of active metal, increased activity per unit volume, high mass/heat transfer.
合成了一种高多孔的 NiAl2O4 尖晶石结构，并将其用作整体式反应器中甲烷自热干法转化（ATDRM）催化剂的载体。制备了一系列含有不同金属种类的催化剂 X/NiAl2O4@整体（X：Ni、Co、Pt、Rh 和 Ru）。由于 NiAl2O4 具有高表面积和大孔隙率，因此它能使活性金属物种高度分散，且尺寸分布均匀。这些特点使催化剂能够通过改善反应物的吸附和反应速率来最大限度地提高催化性能。更值得注意的是，与传统的氧化铝载体相比，NiAl2O4 载体提高了催化剂的酸性，从而在 ATDRM 过程中延缓了焦炭的形成，从而延长了催化剂的寿命。在 X/NiAl2O4 催化剂上，费化物、CH4 和 CO2 的转化率按 Rh > Ni > Ru > Co > Pt 的顺序增加。值得注意的是，使用 NiAl2O4 作为支撑材料时，廉价的 Ni 催化剂与昂贵的贵金属 Rh 相比，CH4 转化率略低，但不相上下：镍的转化率为 93.7%，而 Rh 的转化率为 95.2%。此外，与固定床反应器相比，使用整体反应器可显著提高甲烷转化率，这是因为活性金属分布更均匀，单位体积活性提高，传质/传热高。
{"title":"Synthesis of Coke‐Resistant Catalyst Using NiAl2O4 Support for Hydrogen Production via Autothermal Dry Reforming of Methane","authors":"Yasin Khani, Sumin Pyo, Farzad Bahadoran, Kanghee Cho, Kwang-Eun Jeong, Young-Kwon Park","doi":"10.1002/cctc.202401015","DOIUrl":"https://doi.org/10.1002/cctc.202401015","url":null,"abstract":"A highly porous NiAl2O4 spinel structure was synthesized and employed as a support for catalysts in the autothermal dry reforming of methane (ATDRM) in a monolithic‐type reactor. A series of catalyst with various metal species, X/NiAl2O4@monolith (X: Ni, Co, Pt, Rh, and Ru), was prepared. NiAl2O4 support provides a high dispersion of active metal species with a uniform size distribution, due to its high surface area, and large pore volume. These features enable catalysts to maximize catalytic performance by improving the adsorption and reaction rates of reactants. More notably, the use of NiAl2O4 support enhanced catalyst longevity by retarding coke formation during the ATDRM, due to its improved catalyst acidity compared to conventional alumina support. The conversion of feeed, CH4 and CO2 on X/NiAl2O4 catalysts increases in the order of Rh > Ni > Ru > Co > Pt. Notably, the inexpensive Ni catalyst exhibits slightly lower but comparable CH4 conversion to the expensive noble metal Rh when using NiAl2O4 as a supporting material: 93.7% for Ni vs. 95.2% for Rh. Moreover, applying monolithic reactors considerably increased methane conversion compared with fixed bed reactors due to the better distribution of active metal, increased activity per unit volume, high mass/heat transfer.","PeriodicalId":141,"journal":{"name":"ChemCatChem","volume":"9 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jie Zhou, Yuanyuan Wu, Yonghong Liu, Na Li, Zhen Yang, Jiadi Ying, Xiaorong Ren, Tao Zhang, Wei Xu, Jinyang Chen, Xingzhong Cao, Runsheng Yu, Minfeng Zeng
N‐doped porous carbon shows great potential in the field of heterogenous supports due to its high porosity, large surface area, rich active sites, and strong chelation with catalytic active metals species. Here, we successfully fabricated novel N‐doped porous carbon derived from alginate/melamine blends with different mass ratio by simple carbonization and activation process. Hierarchical porous structure of the derived N‐doped carbon has been confirmed with the SEM, TEM and N2 adsorption characterization. After Na2PdCl4 solution impregnation and further reduction process, Pd0 nanoparticles have been uniformly immobilized on the SMCNC support to produce novel Pd@SAMNC catalyst. The optimated Pd@SAMNC‐0.6 possesses a high N content (5.13%), Pd content (5.90%), large BET specific surface area of 1884.5 m2/g. Positron annihilation lifetime spectroscopy (PALS) investigation of the porous carbon materials provided the sub‐nano level microporous information proofs of Pd@SAMNC‐0.6 had the capability to provide more active sites for reactions than commercial Pd@AC. Pd@SAMNC‐0.6 catalyst showed superior catalytic efficiency in Heck coupling reaction between aromatic halides and alkenes and can be recycled for 17 runs without significant decrease in catalytic efficiency.
掺杂 N 的多孔碳具有高孔隙率、大比表面积、丰富的活性位点以及与催化活性金属物种的强螯合作用，因此在异质支撑领域具有巨大潜力。在这里，我们通过简单的碳化和活化过程，成功地制备了由不同质量比的海藻酸盐/三聚氰胺混合物衍生的新型 N 掺杂多孔碳。通过扫描电镜、电子显微镜和 N2 吸附表征，确认了衍生 N 掺杂碳的分层多孔结构。经过 Na2PdCl4 溶液浸渍和进一步还原处理后，Pd0 纳米粒子被均匀地固定在 SMCNC 载体上，生成了新型 Pd@SAMNC 催化剂。优化后的 Pd@SAMNC-0.6 具有较高的 N 含量（5.13%）、Pd 含量（5.90%）和较大的 BET 比表面积（1884.5 m2/g）。多孔碳材料的正电子湮没寿命光谱（PALS）研究提供了亚纳米级微孔信息，证明 Pd@SAMNC-0.6 比商用 Pd@AC 能够为反应提供更多的活性位点。Pd@SAMNC-0.6 催化剂在芳香卤化物与烯烃的赫克偶联反应中表现出卓越的催化效率，并且可以循环使用 17 次而不会显著降低催化效率。
{"title":"Pd nanoparticle supported on N‐doped carbon derived from sodium alginate/melamine blends as efficient heterogeneous catalyst for Heck reactions","authors":"Jie Zhou, Yuanyuan Wu, Yonghong Liu, Na Li, Zhen Yang, Jiadi Ying, Xiaorong Ren, Tao Zhang, Wei Xu, Jinyang Chen, Xingzhong Cao, Runsheng Yu, Minfeng Zeng","doi":"10.1002/cctc.202401358","DOIUrl":"https://doi.org/10.1002/cctc.202401358","url":null,"abstract":"N‐doped porous carbon shows great potential in the field of heterogenous supports due to its high porosity, large surface area, rich active sites, and strong chelation with catalytic active metals species. Here, we successfully fabricated novel N‐doped porous carbon derived from alginate/melamine blends with different mass ratio by simple carbonization and activation process. Hierarchical porous structure of the derived N‐doped carbon has been confirmed with the SEM, TEM and N2 adsorption characterization. After Na2PdCl4 solution impregnation and further reduction process, Pd0 nanoparticles have been uniformly immobilized on the SMCNC support to produce novel Pd@SAMNC catalyst. The optimated Pd@SAMNC‐0.6 possesses a high N content (5.13%), Pd content (5.90%), large BET specific surface area of 1884.5 m2/g. Positron annihilation lifetime spectroscopy (PALS) investigation of the porous carbon materials provided the sub‐nano level microporous information proofs of Pd@SAMNC‐0.6 had the capability to provide more active sites for reactions than commercial Pd@AC. Pd@SAMNC‐0.6 catalyst showed superior catalytic efficiency in Heck coupling reaction between aromatic halides and alkenes and can be recycled for 17 runs without significant decrease in catalytic efficiency.","PeriodicalId":141,"journal":{"name":"ChemCatChem","volume":"7 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paula Vidal, Ana Robles-Martín, Laura Fernandez-Lopez, Jose L. Gonzalez-Alfonso, David Almendral, Ruben Muñoz-Tafalla, Francisco J. Plou, Víctor Guallar, Manuel Ferrer
Polyethylene terephthalate (PET) pollution is a global challenge. Advancing the bioprospecting of PET‐degrading enzymes through metagenomics and using computational and functional methods to identify key positions influencing the catalytic rate and selectivity are part of the solution. Here, we report PETase activity in the metagenomic lipase LipMRD9, which exhibits peak activity at 30 °C and pH 9.0 and has a denaturation temperature of 42 °C. In addition to acting on long‐chain triglycerides (up to 13 units (U)/mg, pH 8.0, 30 °C) and a wide range of 34 other esters (up to 228 U/g), LipMRD9 hydrolyses mono(2‐hydroxyethyl) terephthalate (57 U/g) and bis(2‐hydroxyethyl) terephthalate (131 U/g). It also efficiently deconstructs GoodFellow amorphous submicro‐ and nanosized PET particles (984/2238 µM degradation products at 30/40 °C, pH 7.0, 21.5 h) and films (112/198 µM degradation products at 30/40 °C, pH 7.0, 7 days). Through molecular modelling and experimental analysis, the active site of LipMRD9 was revealed, identifying a key residue contributing to its PETase activity compared with those of its closest homologues. This residue plays a crucial role in determining the distinct profiles of degradation products from PET hydrolysis and should be studied in other PETases for its influence on the catalytic process.
聚对苯二甲酸乙二醇酯（PET）污染是一项全球性挑战。通过元基因组学推进 PET 降解酶的生物勘探，并利用计算和功能方法确定影响催化率和选择性的关键位置，是解决方案的一部分。在这里，我们报告了元基因组脂肪酶 LipMRD9 的 PET 酶活性，它在 30 °C 和 pH 值 9.0 时表现出峰值活性，变性温度为 42 °C。除了作用于长链甘油三酯（高达 13 个单位 (U)/mg，pH 值 8.0，30 °C）和范围广泛的 34 种其他酯类（高达 228 U/g）之外，LipMRD9 还能水解对苯二甲酸单（2-羟乙基）酯（57 U/g）和对苯二甲酸双（2-羟乙基）酯（131 U/g）。它还能有效分解 GoodFellow 无定形亚微米级和纳米级 PET 颗粒（984/2238 µM 降解产物，30/40 °C，pH 值 7.0，21.5 小时）和薄膜（112/198 µM 降解产物，30/40 °C，pH 值 7.0，7 天）。通过分子建模和实验分析，揭示了 LipMRD9 的活性位点，确定了一个与其最接近的同源物相比有助于提高 PET 酶活性的关键残基。该残基在决定 PET 水解过程中降解产物的不同特征方面起着至关重要的作用，因此应研究其他 PET 酶对催化过程的影响。
{"title":"Unlocking a Key Residue in a Lipase for Efficient Polyethylene Terephthalate (PET) Hydrolysis and Influencing Depolymerization Product Profiles","authors":"Paula Vidal, Ana Robles-Martín, Laura Fernandez-Lopez, Jose L. Gonzalez-Alfonso, David Almendral, Ruben Muñoz-Tafalla, Francisco J. Plou, Víctor Guallar, Manuel Ferrer","doi":"10.1002/cctc.202400765","DOIUrl":"https://doi.org/10.1002/cctc.202400765","url":null,"abstract":"Polyethylene terephthalate (PET) pollution is a global challenge. Advancing the bioprospecting of PET‐degrading enzymes through metagenomics and using computational and functional methods to identify key positions influencing the catalytic rate and selectivity are part of the solution. Here, we report PETase activity in the metagenomic lipase LipMRD9, which exhibits peak activity at 30 °C and pH 9.0 and has a denaturation temperature of 42 °C. In addition to acting on long‐chain triglycerides (up to 13 units (U)/mg, pH 8.0, 30 °C) and a wide range of 34 other esters (up to 228 U/g), LipMRD9 hydrolyses mono(2‐hydroxyethyl) terephthalate (57 U/g) and bis(2‐hydroxyethyl) terephthalate (131 U/g). It also efficiently deconstructs GoodFellow amorphous submicro‐ and nanosized PET particles (984/2238 µM degradation products at 30/40 °C, pH 7.0, 21.5 h) and films (112/198 µM degradation products at 30/40 °C, pH 7.0, 7 days). Through molecular modelling and experimental analysis, the active site of LipMRD9 was revealed, identifying a key residue contributing to its PETase activity compared with those of its closest homologues. This residue plays a crucial role in determining the distinct profiles of degradation products from PET hydrolysis and should be studied in other PETases for its influence on the catalytic process.","PeriodicalId":141,"journal":{"name":"ChemCatChem","volume":"21 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nitrous oxide (N2O) has gained increasing attention as a non‐carbon dioxide greenhouse gas, and catalytic decomposition is an effective method for mitigating its emissions. In this study, Ce‐Pr co‐doped Co3O4 was synthesised via a coprecipitation method and used for the catalytic decomposition of N2O. The experimental results revealed that the N2O decomposition achieved 100% conversion at 400 °C on the catalyst with a Pr/Ce/Co molar ratio of 0.02:0.2:1, exhibiting an 80 °C decrease of T100 compared with that of Co3O4. The introduction of Ce reduced the size and crystallisation of Co3O4 particles, increased the activity of the lattice oxygen of Co3O4, and facilitated the formation of oxygen vacancies, thereby enhancing the activation of N2O. However, the introduction of Ce inhibited the crystallisation of Co3O4 and the surface coverage of CeO2 decreased the exposure degree of N2O molecules to the Co3O4 surface. Co‐doping strategy of Ce‐Pr was performed to alleviate the negative effects of ceria. Consequently, the incorporation of Ce and Pr species enhanced the redox properties of Co3O4, leading to remarkable catalytic performance of N2O decomposition. This study elucidated the interaction between Ce and Pr dopants and Co3O4, and encouraged more attention on designing novel catalysts for N2O mitigation.
{"title":"Ce‐Pr co‐doped Co3O4 with enriched oxygen vacancies for the efficient decomposition of N2O","authors":"Haiqiang Wang, Yuxin Sun, Yunshuo Wu, Zhuoyi Zhang, Xuanhao Wu, Zhongbiao Wu","doi":"10.1002/cctc.202401060","DOIUrl":"https://doi.org/10.1002/cctc.202401060","url":null,"abstract":"Nitrous oxide (N2O) has gained increasing attention as a non‐carbon dioxide greenhouse gas, and catalytic decomposition is an effective method for mitigating its emissions. In this study, Ce‐Pr co‐doped Co3O4 was synthesised via a coprecipitation method and used for the catalytic decomposition of N2O. The experimental results revealed that the N2O decomposition achieved 100% conversion at 400 °C on the catalyst with a Pr/Ce/Co molar ratio of 0.02:0.2:1, exhibiting an 80 °C decrease of T100 compared with that of Co3O4. The introduction of Ce reduced the size and crystallisation of Co3O4 particles, increased the activity of the lattice oxygen of Co3O4, and facilitated the formation of oxygen vacancies, thereby enhancing the activation of N2O. However, the introduction of Ce inhibited the crystallisation of Co3O4 and the surface coverage of CeO2 decreased the exposure degree of N2O molecules to the Co3O4 surface. Co‐doping strategy of Ce‐Pr was performed to alleviate the negative effects of ceria. Consequently, the incorporation of Ce and Pr species enhanced the redox properties of Co3O4, leading to remarkable catalytic performance of N2O decomposition. This study elucidated the interaction between Ce and Pr dopants and Co3O4, and encouraged more attention on designing novel catalysts for N2O mitigation.","PeriodicalId":141,"journal":{"name":"ChemCatChem","volume":"11 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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